meso -Mono-[4-(1,4,7-triazacyclononanyl)]-tri(phenyl)]porphyrin and the respective zinc( ii )-complex: complete characterization and biomolecules binding abilities

We aimed to synthesize a new series of triazacyclononanyl-porphyrins ( 4 and 5 ) with the potential ability to bind DNA. For this, the free-base porphyrin 4 and the corresponding Zn( ii )-complex 5 were synthesized by the Schiff base formation reaction. The binding ability of the porphyrin derivatives 4 and 5 with DNA from calf-thymus was studied by UV-vis and emission spectroscopy. Detailed analysis of the results suggests that the interaction of these systems most probably occurs through π-stacking and secondary hydrogen interaction surface binding with ct-DNA. Moreover, we also demonstrate the substantial ability of porphyrins 4 and 5 to generate 1 O 2 and to photocleave plasmid DNA after irradiation.